1 /*=============================================================================
2 Copyright (c) 2003 Jonathan de Halleux (dehalleux@pelikhan.com)
3 http://spirit.sourceforge.net/
4
5 Use, modification and distribution is subject to the Boost Software
6 License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
7 http://www.boost.org/LICENSE_1_0.txt)
8 =============================================================================*/
9 ///////////////////////////////////////////////////////////////////////////////
10 // This example shows how the assign operator can be used to modify
11 // rules with semantic actions
12 //
13 // First we show the basic spirit without (without any dynamic feature),
14 // then we show how to use assign_a to make it dynamic,
15 //
16 // the grammar has to parse abcabc... sequences
17 ///////////////////////////////////////////////////////////////////////////////
18 #include <iostream>
19
20 #define BOOST_SPIRIT_DEBUG
21 #include <boost/spirit.hpp>
22
23 #include <boost/spirit/include/classic_assign_actor.hpp>
24
main()25 int main()
26 {
27 using namespace BOOST_SPIRIT_CLASSIC_NS;
28 using namespace std;
29
30 rule<> a,b,c,next;
31 const char* str="abcabc";
32 parse_info<> hit;
33 BOOST_SPIRIT_DEBUG_NODE(next);
34 BOOST_SPIRIT_DEBUG_NODE(a);
35 BOOST_SPIRIT_DEBUG_NODE(b);
36 BOOST_SPIRIT_DEBUG_NODE(c);
37
38 // basic spirit gram
39 a = ch_p('a') >> !b;
40 b = ch_p('b') >> !c;
41 c = ch_p('c') >> !a;
42
43 hit = parse(str, a);
44 cout<<"hit :"<<( hit.hit ? "yes" : "no")<<", "
45 <<(hit.full ? "full": "not full")
46 <<endl;
47
48 // using assign_a
49 a = ch_p('a')[ assign_a( next, b)] >> !next;
50 b = ch_p('b')[ assign_a( next, c)] >> !next;
51 c = ch_p('c')[ assign_a( next, a)] >> !next;
52 hit = parse(str, a);
53 cout<<"hit :"<<( hit.hit ? "yes" : "no")<<", "
54 <<(hit.full ? "full": "not full")
55 <<endl;
56
57 return 0;
58 }
59